GHRF test in acromegalic patients for the evaluation of therapeutic results

We studied here the clinical significance of GHRF test in evaluating therapeutic results in patients with acromegaly. Three cases of acromegaly were studied at pre- and posttreatment. Case 1 is a 42 year old woman, and her plasma GH showed slight increases responding to TRH and arginine administration before therapy. Eleven years after the pituitary irradiation, basal plasma GH decreased to low normal ranges and showed no response to the above two agents. Only an insufficient increase in plasma GH was observed after GHRF injection. This case would have pituitary lesions not only in the tumor somatotrophs but also in the normal somatotrophs. Case 2 is a 38 year old man. His plasma GH showed a marked increase after TRH injection. To GHRF administration, however, no clear response was observed. After transsphenoidal adenomectomy, the aberrant responses to TRH was still observed despite the marked GH decrease to the near normal ranges. Interestingly, plasma GH became responsive to GHRF after the operation. It seems that the adenomectomy was inadequate in this case and the normal somatotrophs recovered the responsiveness to GHRF. Case 3 is a 53 year old woman, and she showed aberrant GH responses to TRH and to L-dopa. Her plasma GH clearly increased after GHRF injection. Postoperatively, the abnormal responses of plasma GH disappeared completely, while a normal GH response was observed following GHRF injection.(ABSTRACT TRUNCATED AT 250 WORDS)